$a->text = format_text("$qnumchar. $answer->answer", FORMAT_MOODLE, $formatoptions, $cmoptions->course);
to
$a->text = format_text("<span class=\"a_num\">$qnumchar</span><span class=\"a_num_sep\">.</span> $answer->answer", FORMAT_MOODLE, $formatoptions, $cmoptions->course);
in line 325 of /question/type/multichoice/questiontype.phpto
$a->text = format_text("<span class=\"a_num\">$qnumchar</span><span class=\"a_num_sep\">.</span> $answer->answer", FORMAT_MOODLE, $formatoptions, $cmoptions->course);
What would be the best way to get this done?